Tyler and Purcell, a former state representative, are running in a Nov. 3 special election for a vacancy in the 159th House District. Both are Republicans.

Buddy Carter gave up the seat to seek the 1st District Senate post from which Eric Johnson, a candidate for governor, recently resigned.

"There is a big difference between myself and my opponent," Tyler said at a news conference. "My opponent is a 14-year Democrat in the House who has been gone five years.

"I have always been a conservative, and I would never think about switching parties for personal gain."

Purcell became a Republican a few months before a 2004 GOP primary she lost to Carter.

She said Friday she and other conservative Democrats left the party several years ago because it no longer reflected their values.

"The party left me," she said. "The stands it was taking were out of line with what I have believed in all my life."

She said state Sen. Jack Hill and state Reps. Bob Lane and Butch Parish bolted the Democrats for similar reasons. So did Gov. Sonny Perdue and - many years before - former President Ronald Reagan, she said.

If former Democrats were considered too politically tainted to run as Republicans, "I don't know ... where we would be" as a party, she said.

Pressed concerning whether he was willing to say directly that Purcell switched "for political gain," Tyler merely said she did so "right before" the election.

"That's all I'm going to say," he added. "I'm not going to get into personal attacks."

Asked whether he's been a GOP voter much longer than Purcell, Tyler, 25, said he's voted that way since he was 18.

"I've been a conservative all my life," said Tyler, who has worked on several Republican election campaigns.

Asked whether Purcell is a conservative, too, he replied, "No, she's a Democrat."

Tyler said that, as a legislator, she "voted with" long-time Democratic House Speaker Tom Murphy.

"And that's all the questions I'm going to answer," Tyler said.

Carter raised the same issue against Purcell in 2004. But he has endorsed her in the special election.